So Chris Pine is back in the movie. One of the popular theories surrounding his return is that Maxwell Lord(Pedro Pascal), who is a businessman, finds a way to fulfill Diana's wish in return for something he wants from Themyscira.
And its also possible that Chris Pine may die again at the end of this movie - he may be attached to Maxwell Lord. Diana ends up killing Lord losing Steve in the process. Also, since in modern-day BvS and Justice League, Steve was nowhere to be found, this sounds plausible.
In the comics, Maxwell Lord is associated with Justice League until he betrays them and dies at the hand of Wonder Woman when she snaps his neck off. He has telepathic powers that allow him to control others.
The jet which Diana and Steve are riding in the trailer can be the Invisible jet Diana uses in the comics. The jet was created by Diana herself and can travel at supersonic speeds, can do space travel and has all sorts of weapons.
The golden armor she is seen sporting at the end is her Golden Eagle armor and it first appeared in Kingdom Come comics. The armour gives her wings and allows her to withstand a wide range of weapons. It was created by the Amazonians. I am guessing she needs it against Cheetah.
Kristen Wiig is playing the role of an archaeologist, Barbara Ann Minerva, who idolizes Wonder Woman/Diana. But somehow in her quest to find more about the lost tribe of Amazonians, she manages to injure herself with an ancient relic that curses her with the power of Cheetah which comes with cannibalistic tendencies. Now she blames Diana for her transformation and the cannibalistic urge that came with it.
From the trailer, it looks as if trials will also be held at Themyscira to choose a warrior. Don't know what for though.
As for the action, Patty Jenkins clarified that most of the action and stunts are real and use practical effects with minimal CGI to make it as realistic as possible. Kristen Wiig will sport prosthetics for her yet to be unveiled Cheetah look with little CGI support.
Patty Jenkins also said that Chris's role is not a gimmick and is integral to the story.
The soundtrack in the trailer is an instrumental remix of "Blue Monday" by New Order - a song that was released in 1983 making it the perfect choice for the movie.